On the design of rigid-soft hybrid exoskeleton based on remote cable actuator for gait rehabilitation

Lower-limb exoskeletons for gait rehabilitation have been widely studied, including rigid or soft mechanisms. It is concluded that soft exoskeletons have better modality in human-robot coordination while rigid ones can provide the support force for stability. Therefore, it attracts interests if an exoskeleton can meet the advantages of both the 'soft' and 'rigid' ones. In this paper, we proposed a kind of rigid-soft hybrid structure, which not only meet the 'soft' requirements without joint restriction, but also provide support for the limbs to implement the 'rigid' function. The hybrid exoskeleton is based on no-joint design and assist human limbs by linear cable-driven actuator, which is driven by motor through cable-sheath transmission structure. We separate the motor, control, acquisition and power components from the common exoskeleton system structure and integrated them on a mobile platform. This design can minimize the weight on the human body, where we only keep the actuator of exoskeleton on lower limb. Preliminary experiments validate the feasibility of the proposed system.